Feminism originated at the Seneca Falls Convention in 1848 and it was non-partisan. Indeed neither party really cared much for women's rights at first. Feminists/suffragettes had to campaign for 70+ years after Seneca Falls before they won the right to vote.
It is true that the Republican Party used to have more "progressive" tendencies (see: Teddy Roosevelt). However, as a matter of fact Woodrow Wilson (D) was in office when the 19th Amendment passed, and he gave it his support.
There have been many developments since the 19th Amendment. What's been consistent is that conservatives of either party have always opposed feminism. Modern-day Republicans have taken a firm anti-feminist stance in the culture wars.
To state the obvious: brandishing a gun doesn't make you a feminist.
Supporting abortion rights and equal pay and gender discrimination laws and paid maternity leave and such does.
If you walk around in a va**na suit, then you might look ridiculous but it's likely that you do care about such things.
Learn more here.
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